Search Publications
I Zw 1 observed with XMM-Newton . Low-energy spectral complexity, iron lines, and hard X-ray flares
Brandt, W. N.; Vaughan, S.; Fabian, A. C. +2 more
We present a 20 ks XMM-Newton observation of the prototypical Narrow-Line Seyfert 1 galaxy I Zw 1. The best-fit model to the data is a double blackbody plus a dominant power-law, on which complex soft absorption (possibly a blended edge or absorption lines) and/or OVII emission are superimposed, as well as strong Fe Kα emission. The iron feature i…
The complex X-ray spectrum of NGC 4507
Bianchi, S.; Matt, G.; D'Ammando, F. +1 more
XMM-Newton and Chandra/HETG spectra of the Compton-thin (NH∼4×1023 cm-2) Seyfert 2 galaxy, NGC 4507, are analyzed and discussed. The main results are: a) the soft X-ray emission is rich in emission lines; an (at least) two-zone photoionization region is required to explain the large range of ionization states; b) t…
XMM-Newton spectral and timing observations of the millisecond pulsar PSR J0218+4232
Webb, N. A.; Barret, D.; Olive, J. -F.
We present XMM-Newton MOS imaging and PN timing data of the millisecond pulsar
High-z massive galaxies in the Hubble Deep Field South
Fontana, A.; Vanzella, E.; Cristiani, S. +6 more
A census of massive galaxies at redshift increasingly higher than z∼1 may provide strong constraints for the history of mass assembly and star formation. Here we report the analysis of three galaxies selected in the Hubble Deep Field South at K s≤22 on the basis of their unusually red near-IR color J-K≥3. We have used population synthesis models t…
XMM-Newton EPIC observation of the galaxy cluster A 3667
Finoguenov, A.; Briel, U. G.; Henry, J. P.
The Abell cluster of galaxies A 3667 was observed with XMM-Newton in 6 partially overlapping pointings. We present here the resulting X-ray surface brightness, temperature, entropy and pressure maps and discuss the structure of this cluster on scales from 0.1 to 30 arcmin. Based on these observations we refine the origin of the A 3667 cold front t…
A study of the expanding envelope of Nova V1974 Cyg 1992 based on IUE high resolution spectroscopy
Altamore, A.; Rossi, C.; González-Riestra, R. +2 more
We have carried out a detailed analysis of the IUE archival high resolution spectra of the classical nova V1974 Cyg 1992. The main UV resonance lines show P Cygni profiles in the first days, which change into symmetric pure emission lines, and then slowly become fainter and narrower. Lines of higher ionization species reach their peak luminosity l…
The 3-D ionization structure and evolution of NGC 7009 (Saturn Nebula)
Sabbadin, F.; Turatto, M.; Cappellaro, E. +2 more
Tomographic and 3-D analyses for extended, emission-line objects are applied to long-slit ESO NTT + EMMI high-resolution spectra of the intriguing planetary nebula NGC 7009, covered at twelve position angles. We derive the gas expansion law, the diagnostics and ionic radial profiles, the distance and the central star parameters, the nebular photo-…
Heliospheric conditions that affect the interstellar gas inside the heliosphere
Möbius, E.; Bzowski, M.; Lallement, R. +9 more
The interstellar gas that flows through the heliosphere is strongly affected by ionization close to the Sun, in particular solar photoionization, electron impact, and charge exchange. Therefore, the interpretation of any observation of interstellar gas in the inner heliosphere hinges upon the accurate knowledge of these effects and their variation…
An XMM-Newton observation of the massive binary HD 159176
Gosset, E.; Owocki, S. P.; Rauw, G. +4 more
We report the analysis of an XMM-Newton observation of the close binary HD 159176 (O7 V + O7 V). The observed LX/Lbol ratio reveals an X-ray luminosity exceeding by a factor ∼7 the expected value for X-ray emission from single O-stars, therefore suggesting a wind-wind interaction scenario. EPIC and RGS spectra are fitted cons…
Beyond the iron group: Heavy metals in hot subdwarfs
O'Toole, S. J.
We report the discovery of strong photospheric resonance lines of Ga III, Ge IV, Sn IV and Pb IV in the UV spectra of more than two dozen sdB and sdOB stars at temperatures ranging from 22 000 K to 40 000 K. Lines of other heavy elements are also detected, however in these cases more atomic data are needed. Based on these discoveries, we present a…